There have been times in the last year where the economy lot has been fully packed, and closed to new vehicles. However, I'm thinking that was probably in the winter and you should be ok now. Because the economy lot area is quite big, leave yourself lots of time to circle around looking for a spot, and then for the long but manageable walk to the terminal from there.

Another option would be park and jet, which is the cheaper and more no- frills of the two parking shuttle services, which I believe is only $8.95/day.

Having spent far too much time circling around airport parking lots, I find the heaviest/fullest time to be mid day. Around 1000-1400. The morning arrivals haven't left yet, and the afternoon/evening departures have already arrived.

At the time you suggest, I would guess the parking lot would be at it's emptiest.